The invention relates generally to semiconductor device-based sensors and, more particularly, to gallium nitride material-based transistors that function as chemical sensors and methods associated with the same.
Sensors may be used in many applications, for example, to detect the concentration of a chemical species. The chemical species may be a component of a fluid (e.g., a gas or a liquid) to which the sensor is exposed.
Semiconductor devices have been used as chemical sensors. For example, field effect transistor-based sensors may detect the concentration of a chemical species by measuring changes in drain current (i.e., source-to-drain current) that result from adsorption of the chemical species on the surface of the gate electrode. This adsorption may lead to a change in drain current. The change in the drain current may be related to the concentration of the adsorbed chemical species which, in turn, may be related to the concentration of the chemical species in the medium (e.g., fluid) being characterized.